Tutorial 3: Power and Sample Size for the Two …

← Back to document page

Tutorial 3: Power and Sample Size for the Two- Sample t-test with Equal Variances Preface Power is the probability that a study will reject the null hypothesis . The estimated probability is a function of Sample size, variability, level of significance, and the difference between the null and alternative hypotheses. Similarly, the Sample size required to ensure a pre-specified Power for a hypothesis test depends on variability, level of significance, and the null vs. alternative difference. In order to understand our terms, we will review these key components before embarking on a numeric example of Power and Sample size estimation for the two independent- Sample case with unequal variances. Overview of Power Analysis and Sample Size Estimation A hypothesis is a claim or statement about one or more population parameters, a mean or a proportion.

Tutorial 3: Power and Sample Size for the Two-sample t-test . with Equal Variances . Preface . Power is the probability that a study will reject the null hypothesis.

  Null, Hypothesis, Null hypothesis